nested aliases in /etc/aliases: which order?

Question

my /etc/aliases (ubuntu 12.04 lts) already contains some aliases redirecting to root:

postmaster: root
clamav: root
monit: root

now I want to add another alias that redirects all root messages to the user mainuser, because root doesn't check its email regularly:

root: mainuser

does this work? does it matter whether the new alias is added at the top of the file or at the bottom?

Answer 1

The order doesn't matter for postfix or exim, but it may matter for other mail servers.